1. Animal Reproduction Laboratory, Texas AgriLife Research, Beeville 78102
2. Departments of Animal Science, Texas A&M University, College Station 77843
3. Poultry Science, and Texas A&M University, College Station 77843
4. Texas AgriLife Extension, Texas AgriLife Research and Extension Center, Corpus Christi 78406
5. Electrical and Computer Engineering, Texas A&M University, College Station 77843
6. Division of Animal Sciences, University of Missouri, Columbia 65211